Damian Thompson is smart, writes with a wit that often has me guffawing, and is lucky to have great people to work with at the Catholic Herald. But his raggety piece in the most recent issue of the paper, repeated on his blog, is a disgrace. While Thompson was once described as a "blood crazed ferret" this week's article reads more like the Monday Club on magic mushrooms.

At the outset – perhaps by mistake? – he gives the impression that the plight of 70 migrants drowning at sea, while nine ships passed by within sight, is just one of those things. He takes a mild swipe at the Italian Catholic bishops, while admitting that their statement did, in fact, strike the right tone. Bouncing on, he criticises the church's campaign for regularisation of immigrants, and Islam's "adversarial quality". Anyone who disagrees with him, he suggests, must be a modernist grounded in the liberalism of the 60s. For this friend of Catholic traditionalists, this is the ultimate put-down.

But Damian Thompson is plain wrong.

First, it is worth remembering that the philosophical base of most mainstream Catholicism emerges from the thought of St Thomas Aquinas in the 13th century. In turn Aquinas built much of his theology on insights gleaned from translations of Greek philosophy undertaken – and saved – by Muslim scholars. The roots of European culture have long been intertwined with Islam, and to positive effect. Dusting off crusaders' crosses will not do.

Second, in the Thomist tradition, nation states are never an end in themselves but always defined against a greater "common good", an eternal benchmark, as to what constitutes justice. This is why Pope John Paul II argued that a starving person who migrates in order to feed his family breaks no (moral) law.

Third, Thompson tries to argue that the political cause of migrants is marginal because it has not been backed by the left. In fact, politicians from across the spectrum – Baroness Shirley Williams, Mayor Boris Johnson, Cardinal Murphy O'Connor and moderate trade unions – have all been making the case for regularisation. Crucially, they advance that view while also noting the needs of European citizens legally allowed to be here but struggling in the midst of Gordon Brown's recession, and asylum seekers and refugees caught up in the managerial mess otherwise known as the Home Office and its associated quangos responsible for immigration. Thompson muddles them up, weakening his argument even further.

Lastly, Damian Thompson needs to move from Notting Hill to Bethnal Green to learn a bit more about Britain. Muslims in this country are a young, vibrant, diverse community with much to offer the nation. In parts of the country they face intense poverty and the harsh ignorance of the regions in which they have settled. In this regard they share a historical experience with the Irish before them. In the 19th century thousands crossed the Irish sea to find jobs, brought their religion with them, worked hard, and stayed. But the problem with Catholics of the same mind as Damian Thompson is that they didn't treat the Irish with any respect either. Buried in their publicly declared loyalty to "proper church teaching" was an ungodly discrimination grounded in petty localisms, economic class and social insecurity.

A genuinely orthodox Catholicism would build rich relationships with Muslims. Writers like Damian Thompson ought to be at the forefront of such efforts rather than peddling views which, in the long term, sow resentment rather than reason.